Cure or Break-In a Barrel?

So I’ve read and heard about “breaking in” a barrel, where you clean a weapon after every round fired for the first couple dozen rounds (or another cycle like ever 1 round for the first 5, every 2 rounds the next 10, every 3 the next 15, etc).

The most cogent explanation I’ve seen is that this keeps copper from the bullet jacket from catching on the less polished parts of a new barrel until the shooting and cleaning had smoothed those parts out. If you just fire a few dozen rounds and clean it after the first range day, you risk getting copper other fouling sorta… trapped in the barrel or throat as those surfaces just get hammered down flat by each round.

I’ve alternately heard of “curing” a barrel with much the same process.

This was explained that if the barrel isn’t hardened or otherwise heat-treated, the first several dozen rounds will do that to the barrel. The heat causes a chemical and grain change in the barrel’s material. The rationale given was that by cleaning it with oil after each round (and between successively greater batches of rounds), you’re heat-treating the barrel metal with oil instead of with copper and lead and carbon fouling and unburnt powder etc.

And I’ve also heard that they’re both bunk, and breaking in just gets everything adjusted to the state that the forces of firing will settle it into.

So what’s your take on curing or breaking-in a barrel?

1 Like

I don’t get that involved, but I do break in the barrel. Since I’m in California and can only use 10 round mags, I’ll do a quick swab after each mag and after 50 rounds I’ll field strip it and clean it. Then do that same process again. After that it’s good to go.

3 Likes

I don’t subscribe to the “break in the barrel” philosophy. In fact, I read an article about “copper fouling” that actually made sense to me. The article stated that the copper actually fills in the microscopic imperfections in the barrel and imparts additional slickness. Their recommendation was that when you are cleaning a barrel if you start seeing green on your patch instead of black, stop. The green is the copper.

The whole idea could be hogwash, but it sounded logical to me and I’m following that advice.

Mike

2 Likes

I hear ya, @Michael1 ! My intent with this thread was largely just to hear what other people have heard. As far as I’m concerned there are no wrong answers!

I mean unless someone from like HK manufacturing is here to chime in. That might carry some weight.

1 Like

Unless you’re firing a large number of rounds very fast you aren’t going to get that barrel hot enough to do any sort of heat treat.

Break in periods i do subscribe to though. I just keep things well lubed during the first 500 rounds or so.

2 Likes

I never put any thought into breaking in a barrel. Then again, I never heard about that being a thing until recently…

2 Likes

You’ll need to break the barrel in properly before doing any of the heat treatment/curing processes otherwise you just harden all of the rough spots and ensure it will never shoot accurately and will need frequent cleaning.

As low as the pressures and velocities are with pistol rounds I cant’ see where it would be of any significant benefit.

To expedite break in with pistols I just give the barrel a wet mopping with lapping compound before firing and then after about every fifth round for a total of 50 rounds cleaning well between each set of five.

2 Likes

I was told, by several people having skill and experience with firearms, is that “breaking in” a firearm is more about allowing all the moving parts to become seated than it is about any individual component. They said to think of the new gun like a new engine: don’t push it to the max right off but start out moderately and gradually build up to maximum performance, usually somewhere between 200 - 500 rounds. After 500 rounds, if the weapon won’t reliably perform to maximum standard there is likely a mechanical defect. Time to call a gunsmith!

Regards.

2 Likes

That might apply to semi auto pistols but in rifles break in definitely applies to properly conditioning the barrel from the beginning to avoid accuracy and fouling problems.

Semi Auto handguns have a whole lot of moving parts and no amount of machining can get all of them to mesh perfectly so wear is required for them to get to optimum performance.

2 Likes

Absolutely correct, and thank you. In my head I was thinking about semi auto pistols, I just neglected to state that in my post. In future I’ll remember to be more specific.:flushed:

Regards.

2 Likes

Just playing off of your ball David. :+1:

2 Likes

Of course; that’s what we’re here for: give and take, learn and share.

Regards.

3 Likes

I always break-in pistols I intend to use for target / matches, but not as much for EDC because there are two different dynamics at work one is accuracy which means focusing on the bbl, the other is reliability which focuses on the action. Since I would seldom if ever try to EDC something with an 8" bbl the two protocols usually don’t apply to the same weapon. Bbl break-in is easier and takes a lot less ammo as it’s all about smoothing out rough spots, making sure the crown is good and getting consistent shot placement. Once you’re done here it’s shoot and clean… rinse and repeat. EDC is a whole 'nother critter which includes all the mechanicals as well as holsters and externals like snag-points. The newer “melted” profiles are pretty snag resistant, but never take anything for granted.

3 Likes